In the manufacture of garments, and more particularly trousers or the like, the most commonly used method to produce the fly structure is to utilize flypieces which are cut separately from the trouser front panels. One half of a slide fastener stringer is attached in a predetermined position on the fly piece and one edge of the flypiece is provided with overstitching or serging along one longitudinal edge. The other edge of the fly piece is then secured to the trouser front panel in the fly area to complete the installation of the fly flap and the slide fastener on the trouser front panel. The stitching of the slide fastener to the flypiece and the serging of the edge can be accomplished in one operation or in sequential operations.
In attaching the slide fastener stringers to the flypieces the usual method is to feed the flypieces one after another to a sewing machine and stitch them to a continuous length of slide fastener stringer. After the flypieces have been attached to the slide fastener, the slide fastener stringer is severed between the flypieces to provide independent flypieces each having a predetermined length of a slide fastener stringer attached thereto.
Attempts have been made to utilize front panels having the flypieces cut integral therewith. However this presents a problem in trying to utilize a continuous slide fastener stringer for attachment to the flypieces. The length of the leg portion makes it extremely difficult to attach the slide fastener stringer to the fly pieces closely following each other and then to separate the successsive assemblies. Thus while machines have been utilized to automatically feed the small separate fly pieces and the slide fastener stringer to a sewing machine, the feeding of fly pieces integrally attached to a front panel together with automatic feeding of the slide fastener stringer from a continuous supply to a sewing machine has not lent itself to mechanization.